1. Filed of the Invention
The invention, in general, relates to a novel tub for washing fluid and, more particularly to a tub of the kind referred to for rotatably accommodating a washing machine drum and provided at its exterior wall with rib structures.
2. The Prior Art
A washing fluid tubs made of non-metallic materials for washing machines is well known in the art. The tub is made of a synthetic material and is mounted as a molded part in the interior of a washing machine. The structure of the tub is such as to accommodate components or aggregates cooperating with the tub thereon. The tub is characterized by an opening in its axis of rotation for receiving the drive shaft of the rotatable drum disposed in the tub. Moreover, brackets may be arranged below the tub for receiving a drive motor, for instance connected to the drum by a fan belt or the like. The tub is also provided with at least one connecting pipe for feeding and removing the washing fluid.
In order to impart to the rear wall of the tub the rigidity or strength required rotatably to support the drum thereon, the tub, as disclosed, for instance, by German patent specification DE 199 60 501 A1, is provided with rib structures which lend stiffness or structural strength to the rear area of the tub in particular. Such a washing fluid tub, in a washing machine which is loaded through the sidewall of the drum, is mounted within the housing of the machine with the loading opening being disposed at the upper side of the cylindrical wall. Since in such an arrangement requires opening of the tub for placing laundry into the drum, it is possible that when loading wet laundry or adding water through the opening water may drip or swill between housing and the outer wall of the tub. However, for reasons of electrical safety, it is absolutely necessary that neither water nor humidity reach the electrical components mounted within the machine.
In a front-loading washing machine the loading opening is disposed in the front wall of the washing fluid tub and the opening is sealed with respect to the housing of the machine by a folding bellows seal. In a normal operation it may be assumed that the tub in the housing is protected from water leakage. However, with a leaking feed hose above the tub it is nevertheless possible in a front-loading washing machine that water leaks to the outer surface, particularly in the area of its cylindrical surface, of the washing fluid tub. Here, too, it is absolutely necessary that neither water nor humidity reach any electrical components.
While according to the state of the art the integral rib structures are capable of preventing this, they nevertheless leave room for improvement. A further known possibility is to protect electrical components from penetrating water and humidity by housings, covers or encapsulations. Such measures would, however, not only be relatively complex and, therefore, expensive, but they would also impede heat dissipation. Another known construction proposes an elastic folding bellows between the loading opening of the washing fluid tub and the opening of the housing for preventing the penetration of water in this area. However, since the loading opening is of rectangular configuration a lasting and reliable seal between the surrounding margin of the loading opening and the housing cover cannot be ensured because of possible leakage of the folding bellows.
JP 02305596 A of “Patent Abstracts of Japan” discloses a tub washing machine having a vertical rotational axis. In this case, the drive motor is arranged beneath the bottom of the tub. To prevent condensation water from running along the wall of the tub to the bottom of the tub and in this area from dripping onto the motor, an outwardly directed collar-shaped rib is arranged on the wall of the tub. However, the rib acts rather like a cover in the vicinity of the motor. Water sprays and splashes may easily get below this cover and drip onto the motor. Another disadvantage is that water dripping off the cover precipitates and splashes on the bottom of the housing immediately adjacent the motor.